Python 3.x g='gray' 单个按钮位置（relx=0.85，RELn=0.5，锚定=中心） #---第2帧--- #---第3帧--- frame3=tk.Frame（根，bd=5）#删除了这个bg='#80c1ff'（我用它来查看帧的边框） frame3.place（relx=0，rely=0.2，relheight=0.07，relwidth=1，anchor='nw'） #“停止测量”按钮 #这将在最初禁用，并且仅在正在进行测量时启用 按钮停止=tk.按钮（第3帧，text=“停止测量”，bg='#80c1ff'，fg='红色'，state='disabled'，command=stop\u测量） 按钮位置（relx=0.5，RELn=0.5，锚定=中心） #---第3帧--- #---第4帧--- frame4=tk.Frame（根，bd=5） frame4.place（relx=0，rely=0.3，relheight=0.09，relwidth=1，anchor='nw'） label2=tk.Label（frame4，text=“选择要打印数据的传感器：”） 标签2.位置（relx=0.1，rely=0.3，relwidth=0.3，relheight=0.5） clickedForPlotting=tk.StringVar（） clickedForPlotting.set（选项[0]）#默认值 dropPlot=tk.OptionMenu（第4帧，单击打印，*选项） dropPlot.place（relx=0.5，rely=0.5，anchor='center'） #改天 #dropDownButton=tk.Button（frame4，text=“Plot sensor data”，bg='#80c1ff'，fg='red'，command=single_sensor）#bg='gray' #下拉按钮。放置（relx=0.85，rely=0.5，anchor='center'） #---第4帧--- #第5帧将保存为txt文件 #第6帧将是带有文本字段的区域 #---第6帧--- frame6=tk.Frame（根，bg='#80c1ff'）#稍后删除颜色 frame6.place（relx=0.0，rely=0.4，relheight=1，relwidth=1，anchor='nw'） text_frame=tk.frame（frame6） text_frame.place（relx=0，rely=0，relheight=0.6，relwidth=1，anchor='nw'） text=tk.text（文本框架） text.place（relx=0，rely=0，relheight=1，relwidth=1，anchor='nw'） vsb=tk.滚动条（文本框） vsb.pack（侧边='right'，填充='y'） text.config（yscrollcommand=vsb.set） vsb.config（命令=text.yview） #---第6帧--- 停止=真#“停止”标志。如果未进行测量，则为True root.mainloop（）#这里我们运行我们的应用程序 #---梅因---

我的代码的问题是它确实不一致

有时它会工作得很好。大多数时候，它不会启动。我一直按“测量所有传感器”按钮，它被卡住了。我重新启动了三次，得到了相同的结果。第四次尝试时，它可以工作（通常，我必须按“测量所有传感器”按钮两次）

当我按下

rx

按钮时，它几乎总是失败。有一次，它成功了。相同的代码

即使程序确实成功了。有时它会工作得很好。其他时候，字符的显示速度会比正常情况下慢，当我对传感器（电位计）进行更改时，字符的更改将需要一些时间。然后在缓冲了大量数据后，字符将开始出现混合，程序将崩溃

我的代码的行为真的是不一致的，我不明白为什么它有时有效，有时无效

我做每件事都是按部就班的。到目前为止，还没有人能帮助我，甚至没有人能给我一个关于为什么会发生这种行为的指导

---

我已经陷入这个“简单”的问题两个月了。我在这一点上感到绝望。如果有人想要贝宝捐款或什么的，为了帮助我，我在。请帮帮我。

您不应该多次调用

measure\u all（）

（与

measure\u single（）

相同），否则它将创建多个同时运行的定期任务（调用

readSerial（）

）。

import tkinter as tk
import tkinter.ttk as ttk
import serial.tools.list_ports #for a list of all the COM ports
from tkinter import scrolledtext
from time import sleep


#to be used on our canvas
HEIGHT = 800
WIDTH = 800

#hardcoded baud rate
baudRate = 9600

# this is the global variable that will hold the serial object value
ser = None #initial  value. will change at 'on_select()'

after_id = None

#this is the global variable that will hold the value from the dropdown for the sensor select
dropdown_value = None



# --- functions ---

#the following two functtions are for the seria port selection, on frame 1

#this function populates the combobox on frame1, with all the serial ports of the system
def serial_ports():
    return serial.tools.list_ports.comports()


#when the user selects one serial port from the combobox, this function will execute
def on_select(event=None):
    global ser
    COMPort = cb.get()
    string_separator = "-"
    COMPort = COMPort.split(string_separator, 1)[0] #remove everything after '-' character
    COMPort = COMPort[:-1] #remove last character of the string (which is a space)
    ser = serial.Serial(port = COMPort, baudrate=9600, timeout=0.1)


def readSerial():
    global after_id
    try:
       ser_bytes = ser.readline()
       ser_bytes = ser_bytes.decode("utf-8")
    except UnicodeExceptionError:
       print("Oops")
    text.insert("end", ser_bytes)
    if vsb.get()[1]==1.0: #if the scrollbar is down to the bottom, then autoscroll
       text.see("end")
    after_id=root.after(50,readSerial)

# this function is triggered, when a value is selected from the dropdown
def dropdown_selection(*args):    
   global dropdown_value
   dropdown_value = clicked.get()
   button_single['state'] = 'normal' #when a selection from the dropdown happens, change the state of the 'Measure This Sensor' button to normal


# this function is triggered, when button 'Measure all Sensors' is pressed, on frame 2
def measure_all():    
   global stop_
   stop_ = False
   button_stop['state']='normal' #make the 'Stop Measurement' button accessible
   ser.write("rf".encode()) #Send string 'rf to arduino', which means Measure all Sensors
   sleep(0.05) # 50 milliseconds
   readSerial() #Start Reading data


# this function is triggered, when button 'Measure this Sensor' is pressed, on frame 2
def measure_single():    
   global stop_
   stop_=False
   button_stop['state']='normal'
   ser.write(dropdown_value.encode()) #Send string 'rf to arduino', which means Measure all Sensors!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
   readSerial()


# this function is triggered, when button 'STOP measurement(s)' is pressed, on frame 2
def stop_measurement():    
    global stop_
    stop_=True
    button_stop['state']='disabled'
    ser.write("c".encode())
    root.after_cancel(after_id) #do i need after_id to be global?
# --- functions ---



# --- main ---
root = tk.Tk() #here we create our tkinter window
root.title("Sensor Interface")

#we use canvas as a placeholder, to get our initial screen size (we have defined HEIGHT and WIDTH)
canvas = tk.Canvas(root, height=HEIGHT, width=WIDTH)
canvas.pack()

#we use frames to organize all the widgets in the screen

'''
relheight, relwidth − Height and width as a float between 0.0 and 1.0, as a fraction of the height and width of the parent widget.
relx, rely − Horizontal and vertical offset as a float between 0.0 and 1.0, as a fraction of the height and width of the parent widget.
'''

# --- frame 1 ---
frame1 = tk.Frame(root)
frame1.place(relx=0, rely=0.05, relheight=0.03, relwidth=1, anchor='nw') #we use relheight and relwidth to fill whatever the parent is - in this case- root

label0 = tk.Label(frame1, text="Select the COM port that the device is plugged in: ")
label0.config(font=("TkDefaultFont", 8))
label0.place(relx = 0.1, rely=0.3, relwidth=0.3, relheight=0.5)


cb = ttk.Combobox(frame1, values=serial_ports())
cb.place(relx=0.5, rely=0.5, anchor='center')
# assign function to combobox, that will run when an item is selected from the dropdown
cb.bind('<<ComboboxSelected>>', on_select)
# --- frame 1 ---



# --- frame 2 ---
frame2 = tk.Frame(root, bd=5) #REMOVED THIS bg='#80c1ff' (i used it to see the borders of the frame)
frame2.place(relx=0, rely=0.1, relheight=0.07, relwidth=1, anchor='nw')

#Button for 'Measure All Sensors'
#it will be enabled initially
button_all = tk.Button(frame2, text="Measure all Sensors", bg='#80c1ff', fg='red', state='normal', command=measure_all)  #bg='gray'
button_all.place(relx=0.2, rely=0.5, anchor='center')

#label
label1 = tk.Label(frame2, text="OR, select a single sensor to measure: ")
label1.config(font=("TkDefaultFont", 9))
label1.place(relx = 0.32, rely=0.3, relwidth=0.3, relheight=0.4)

#dropdown
#OPTIONS = [0,1,2,3,4,5,6,7]
OPTIONS = list(range(8)) #[0,1,2,3,4,5,6,7]
clicked = tk.StringVar(master=frame2) # Always pass the `master` keyword argument, in order to run the function when we select from the dropdown
clicked.set(OPTIONS[0]) # default value
clicked.trace("w", dropdown_selection) #When a value from the dropdown is selected, function dropdown_selection() is executed
drop = tk.OptionMenu(frame2, clicked, *OPTIONS)
drop.place(relx = 0.65, rely=0.25, relwidth=0.08, relheight=0.6)

#Button for 'Measure Single Sensor'
#this will be disabled initially, and will be enabled when an item from the dropdown is selected
button_single = tk.Button(frame2, text="Measure this Sensor", bg='#80c1ff', fg='red', state='disabled', command=measure_single) #bg='gray'
button_single.place(relx = 0.85, rely=0.5, anchor='center')
# --- frame 2 ---


# --- frame 3 ---
frame3 = tk.Frame(root, bd=5) #REMOVED THIS bg='#80c1ff' (i used it to see the borders of the frame)
frame3.place(relx=0, rely=0.2, relheight=0.07, relwidth=1, anchor='nw')

#Button for 'STOP Measurement(s)'
#this will be disabled initially, and will be enabled only when a measurement is ongoing
button_stop = tk.Button(frame3, text="STOP measurement(s)", bg='#80c1ff', fg='red', state='disabled', command=stop_measurement)
button_stop.place(relx=0.5, rely=0.5, anchor='center')
# --- frame 3 ---



# --- frame 4 ---
frame4 = tk.Frame(root, bd=5)
frame4.place(relx=0, rely=0.3, relheight=0.09, relwidth=1, anchor='nw')

label2 = tk.Label(frame4, text="Select a sensor to plot data: ")
label2.place(relx = 0.1, rely=0.3, relwidth=0.3, relheight=0.5)

clickedForPlotting = tk.StringVar()
clickedForPlotting.set(OPTIONS[0]) # default value
dropPlot = tk.OptionMenu(frame4, clickedForPlotting, *OPTIONS)
dropPlot.place(relx=0.5, rely=0.5, anchor='center')

#CHANGE LATER
#dropDownButton = tk.Button(frame4, text="Plot sensor data", bg='#80c1ff', fg='red', command=single_Sensor) #bg='gray'
#dropDownButton.place(relx = 0.85, rely=0.5, anchor='center')
# --- frame 4 ---


#frame 5 will be the save to txt file


#frame 6 will be the area with the text field
# --- frame 6 ---
frame6 = tk.Frame(root, bg='#80c1ff') #remove color later
frame6.place(relx=0.0, rely=0.4, relheight=1, relwidth=1, anchor='nw')

text_frame=tk.Frame(frame6)
text_frame.place(relx=0, rely=0, relheight=0.6, relwidth=1, anchor='nw')
text=tk.Text(text_frame)
text.place(relx=0, rely=0, relheight=1, relwidth=1, anchor='nw')
vsb=tk.Scrollbar(text_frame)
vsb.pack(side='right',fill='y')
text.config(yscrollcommand=vsb.set)
vsb.config(command=text.yview)
# --- frame 6 ---




stop_=True # 'Stop' flag. True when no measuring is happening

root.mainloop() #here we run our app
# --- main ---